Vet Clin Exot Anim 7 (2004) 87–104

Wound healing and management in

psittacine birds
Tracey K. Ritzman, DVM, Diplomate ABVP-Avian
Practice
Avian & Exotic Pet Medicine Service Angell Memorial Animal Hospital,
350 South Huntington Avenue, Boston, MA 02130, USA

Wound management in the avian patient requires a thorough un-

derstanding of the mechanisms of wound healing in birds and knowledge
of treatment options. For psittacines, potential causes of wounds of
dermatologic origin include trauma, bite wounds inflicted by other animals
in the environment, self-inflicted wounds, constriction injury, bacterial,
fungal, parasitic and viral infections, cutaneous neoplasia, and thermal
injury [1]. The unique anatomy of avian skin and its inflammatory processes
present challenges to the successful treatment or repair of skin lesions.
Wound healing is a complex process of host response to injury, which leads
to regeneration of tissue, vascular supply, and epithelialization [2]. Selec-
tion of a treatment plan for optimization of wound healing requires an
understanding of the specific tissue-healing processes in the avian patient.
Protection of the wound area with bandages during the healing process is
crucial to management of wounds in companion bird species [3]. Patients
with self-inflicted wounds can be challenging to treat, as they are prone to
focusing their attention on the wound site, often causing disruption of the
wound or bandage materials.

Anatomy of the avian integument

Although similar in basic structure to other higher vertebrates, avian
integument is more delicate and thinner than mammalian, and this creates
additional challenges with wound management. Avian skin is comprised of
two main anatomic layers: an epidermis, and dermis [4–6]. A subcutaneous
layer with its neurovascular supply is located below the dermis layer.

E-mail address: tritzman@angell.org (T.K. Ritzman).

1094-9194/04/$ - see front matter Ó 2004 Elsevier Inc. All rights reserved.
doi:10.1016/j.cvex.2003.08.003
88 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

The epidermis is avascular, and it receives its nutrition from the dermis via
simple diffusion in areas of thin skin or structural adaptations in the thicker
regions [5]. The epidermis consists of living and dead cells, and is only 10
cells thick in the domestic fowl [5]. There are two main layers of the
epidermis in birds: the inner living stratum basale (also know as stratum
germinativum), and the outer keratinized, stratum corneum. The stratum
basale contains cells that divide and push cells toward the surface. The most
superficial layer of the epidermis, the stratum corneum, is composed of
horny dead cells. The dermis is the site of feather development from the
dermal papilla. The stratum corneum is thin in many avian species to allow
for the necessary cutaneous flexibility needed on the extremities during flight
[6]. The thin structure of the stratum corneum also aids neurosensation
function of the feathering [6]. The epidermis is thickest in the nonfeathered
areas such as the face, feet, beak, and legs [5].
The avian dermis contains fibrous connective tissue with blood vessels,
nerves, sensory corpuscles, tendons, smooth muscles, and ectodermal feather
follicles with their associated smooth muscles [5]. A unique feature of
the avian dermis is the development of tendons from elastic fibers that
interconnect the smooth muscles of the dermis [6]. There are superficial and
deep layers of the avian dermis. A deeper subcutaneous layer is composed of
loose connective tissue and fat. There is some striated muscle as well, that
functions to control skin tension [6]. Collagen fibers within avian fibrous
connective tissue is similar to that of mammals except the fibrils of collagen are
neatly arranged in a horizontal orientation with a few vertical fibrils. This
differs from the more random collagen arrangement seen in mammals [4–6].
The dense dermal capillary beds in some anatomic areas in birds produces the
red coloration of the wattles, comb, and other skin appendages in some species
[6]. Cutaneous arteries, veins, and nerves are located beneath the muscles at
the base of the dermis and do not branch excessively before reaching the skin
[5]. Anastamoses between vessels is common in the avian skin [5].

The wound-healing process

There are several stages of wound healing. In mammals, there are five
defined stages of tissue healing [7]. These specific stages of mammalian
wound healing include: inflammatory, fibroplastic, epithelialization, contrac-
tion, and remodeling [7]. The wound-healing process in birds is thought to be
similar to that of mammals [8]. Studies to define and evaluate the wound-
healing process in avian species have been based on the chicken model [9].
Many studies of avian wound healing have been based on a single study of the
acute inflammatory reaction in chicken skin conducted by Carlson and Allen
in 1969 [9]. Additional studies have evaluated the response of chicken skin to
injected chemicals, incised wounds, and punch biopsies [10–13].
In the avian model, the wound-healing process in described in three
phases including inflammatory, collagen, and maturation phases [9–11].
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 89

The inflammatory stage is well described in the chicken model. The other two
stages in birds have not been as well documented as the inflammatory stage.

Stages of wound healing

Inflammatory phase
The acute inflammatory response has been studied in chickens. During
the first 12 hours the response is similar between chicken skin and mamm-
alian skin. Immediate vasoconstriction to control hemorrhage occurs. This
is followed by vasodilatation within 30 minutes [13]. After 120 minutes,
polymorphonuclear leukocytes and monocytes begin invading the wound
margins of the injured and necrotic tissue. This leads to active phagocytosis
of necrotic cellular debris and bacteria [9,13].
After 12 hours there is a shift to lymphocytes, monocytes, plasma cells, and
macrophages. During the next 36 hours, necrotic leukocytes that were active
in phagocytosis accumulate at the periphery of the necrotic tissue. These
leukocytes are eventually phagocytized by macrophages and multinucleated
giant cells. The end of the inflammatory phase of healing is characterized by
appearance of fibroblasts in the wound [12,13].

Collagen phase
This second stage of wound healing begins 3 to 4 days after the initial
wound insult. In chickens, the fibroblasts synthesize collagen to form
microfibrils [9]. These microfibrils aggregate to form larger fibers. The
duration of this healing phase is about 2 weeks. During this time, capillaries
develop from bud-like structures from nearby blood vessels. These new
capillaries invade the wound area, and epithelial cells start forming and
migrating across the wound surface from the margins of the wound [12].

Maturation phase
This final phase of wound healing is the longest in duration. This phase is
variable in length, and typically occurs over the course of weeks to months,
and is characterized by remodeling of the collagen bed [12]. During this
phase the number of fibroblasts decrease, while thicker and stronger coll-
agen fibers replace the original, weaker collagen [12,13]. These fibers become
oriented relative to the normal tension on the wound margins [13].

Rate of wound healing

The rate of wound healing is determined by several factors. These factors
include the level of bacterial contamination, the extent of tissue damage or
necrosis, and the patient’s individual healing ability [8,12,14]. Aseptic surgical
90 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

wounds heal most rapidly. Traumatic wounds require cleansing and

debriding, and take longer to heal. Suturing, when appropriate, can reduce
healing time. Protecting the wound during the healing process can aid in
expediting the healing process. Contamination with debris, dirt, dead tissue,
and even suture material [15] may impede healing by stimulating the
development of fistulous tracts [8]. In avian patients, wounds of the distal
extremities with a reduced vascular supply, and nonimmobilized injuries over
joints, the axilla, and the patagia tend to heal more slowly. Conditions in
the avian patient that might impede wound healing include dehydration,
hypoproteinemia, inadequate nutrition, chronic anemia, infection, blood
clots at the wound site, or the presence of necrotic tissue.

Patient examination and wound assessment

Many avian wounds are traumatic in nature, and the initial patient
assessment will involve addressing immediate, life-threatening conditions. A
complete anamnesis will aid in determining the source of the injury, and
a complete physical examination will provide information on the extent and
location of the injuries. Because traumatized birds may present with other
concerns such as shock, dehydration, or malnutrition, stabilization therapy
may be indicated before direct treatment of the wounds [8]. If there is signifi-
cant delay between the time of the injury and presentation to the clinician,
the patient may require extensive stabilization therapy. Balancing the need for
stabilization versus wound care will be crucial for positive patient progress.
Anesthesia may be indicated for birds that do not tolerate restraint or have
severe soft tissue or orthopedic injuries [8]. Emergency management may be
indicated before anesthesia. Temporary bandaging can be applied to patients
that require medical stabilization until more thorough wound treatment can
be performed [8].
Once initial patient stabilization has been performed, the wounds can be
assessed. Wound evaluation includes notation of the location, age, and extent
of the injuries. Orthopedic injuries associated with the wounds should also be
evaluated. Vascular and nerve supply to the wound area will be important in
determining prognosis for healing and return to function, especially with the
extremities. Vascular integrity can be determined by checking for capillary
refill time of the skin, pricking the skin, clipping a toenail, or palpating the
limb for warmth [8]. Measurement of adequate arterial blood supply to the
wound area via measurement of transcutaneous oxygen tension is not feasible
in the avian patient due to small body size.
Fractures, luxations, or soft tissue injury are common sequelae with
traumatic injury. Direct visualization of the skin and underlying tissues will
aid in determining the extent of injury. If necessary, the feathers should be
parted or moistened to view the skin. Bruising in birds occurs, and is charac-
terized by a greenish discoloration of the skin. This greenish discoloration
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 91

is caused by accumulation of biliverdin pigment after the breakdown of

hemoglobin [8]. The greenish appearance involved with bruising develops 2 to
3 days postinjury. This can help to aid in the determination of the time injury
occurred relative to presentation to the clinician [8].
Other diagnostic tests for evaluation of the patient may include radio-
graphy, hematology, bacterial or fungal cultures, viral testing, and cytology.
Biopsy with histopathologic evaluation of tissues may be indicated with
chronic, nonhealing wounds (Fig. 1).

Wound debridement techniques

Debridement is an integral aspect of wound care. Debridement involves the
removal of definitely devitalized tissue, and foreign debris. It is optimal to
preserve tendons, ligaments, nerves, and blood vessels in the adjacent area if
possible. Often wound debridement is performed in stages to allow for
removal of devitalized tissue [3,8]. By staging the wound debridement process
the clinician is able to identify nonviable tissue while preserving potentially
viable tissue. This staged process of debridement is continued until all
nonviable tissue has been removed from the wound [3,8].
General anesthesia is indicated for the wound debridement procedure
for most avian patients to minimize stress, to have optimal control of
hemostasis and tissue handling during the debridement procedure, and to
allow placement of required bandaging materials [3,8]. Before wound
debridement, the skin and surrounding tissue should be prepared. Feathers
adjacent to the wound should be trimmed to prevent contamination of the

Fig. 1. Skin biopsy being performed on the medial tibiotarsal area of an adult Amazon parrot
with chronic ulcerative dermal wounds. (Courtesy of Connie Orcutt, DVM, Dipl. ABVP-
Avian.)
92 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

wound bed. Plucking is not ideal, as this may cause tearing of the skin. A 2-
to 3-cm circumferential featherless zone of healthy skin should be created
around the wound [16]. Large wounds in which there is lack of healthy skin
immediately adjacent to the area may require mobilization of nearby tissue
for coverage. In the psittacine patient, mobilization of adjacent tissue may
not be feasible due to the relative paucity of soft tissue covering the
extremities.
The techniques used to distinguish viable tissue from nonviable tissue in
the avian patient are similar to that of mammals. As mentioned previously,
the breakdown of hemoglobin in the surrounding soft tissues in the avian
patient produces a green discoloration from the release of biliverdin [8]. This
biliverdin discoloration should be distinguished from necrotic tissue, which
is usually black or blanched white [16].
As in mammals, maggot infestation (myiasis) may occur in the warmer
months of the year for birds housed outdoors and exposed to flies. Any
maggots present should be removed during the wound debridement process
[16]. Caution should be exercised when using topical medications in the
psittacine avian patient. The thin dermis in the avian patients allows for
greater potential for absorption of topical medication with potential sys-
temic effects [3]. If infection is suspected in the wound, the optimal time to
collect samples for bacterial or fungal culture is during the debridement
phase of treatment. Ideally, culture samples should be collected after surface
contaminants have been removed, but before the use of topical antimicro-
bial or antifungal products.

Lavage
Wound lavage is a component of the wound debridement process. There
is a wide selection of cleansing agents. Agents that can be used for wound
lavage in the avian patient include: isotonic physiologic saline (0.9% NaCl),
isotonic lactated Ringer’s or Ringer’s solutions, dilute (1:40 or 0.05%)
chlorhexidine, dilute povidone iodine (1% or less), hydrogen peroxide (3%
H2O2), or tap water [8,16]. The goal of wound lavage is the removal or
dilution of foreign debris, blood clots, and infectious agents [8]. It is optimal
to use sterile solutions when possible for wound lavage.
The choice of the lavage solution depends on availability at the time of
the procedure. Solutions without antimicrobial chemical properties rely on
adequate pressure and volume to mechanically remove foreign material.
Fluid solutions with antimicrobial activity have advantages and disadvan-
tages. An advantage is the ability of the medicated solution to be effec-
tive against bacterial or fungal organisms. The disadvantage of chemical
containing solutions is there is potential for negative local tissue reaction,
systemic absorption, toxicosis, or inactivation by organic matter [16].
Povidone iodine has the potential to be absorbed systemically, and its
low pH may exacerbate metabolic acidosis [17,18]. A povidone iodine
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 93

concentration as low as 1–5% has been demonstrated to be toxic to

fibroblasts, which may impede healing [18]. Use should be limited to small
wounds or during surgery preparation.
Chlorhexidine has been shown to have superior antibacterial activity than
povidone iodine with fewer inhibitory effects on wound healing. Chlorhex-
idine at a 0.05% solution is considered to be a safe and very effective irrigating
solution [18]. Hydrogen peroxide is effective primarily against clostridial
infections [17]. Clostridial infections are most likely to occur with deep
puncture wounds [17]. Hydrogen peroxide may be effective in the treatment of
puncture wounds at a concentration of 3% or less [16]. The effervescent
activity of hydrogen peroxide also functions to aid in blood clot removal
[17,18]. Hydrogen peroxide is toxic to fibroblasts and other tissues, and is best
used as a single lavage treatment with deep wounds [16].
Lavage is performed using a large syringe (20–30 mL) and large gauge
hypodermic needle (18 gauge). An ideal liquid pressure of 7 to 8 pounds per
square inch is adequate to irrigate the wound without causing excessive tissue
damage [16]. Ideally, lavage should be repeated several times using large
volumes of the liquid (500–1000 mL) per lavage session. A final lavage with
sterile water or saline is recommended to neutralize the medicated lavage
solution and prevent further cellular destruction [16].

Wound closure
Factors that should be considered with wound closure include the
amount of contamination and infection in the wound, and the amount of
soft-tissue loss and adjacent tissue for closure [19]. The two types of wound
closure include primary closure, in which the wound is sutured immediately
after wound preparation or secondary wound closure (also referred to as
third-intention healing) [3,19].
Primary closure can often be performed immediately after the wound bed
is debrided and prepared. Wounds secondary to thermal injury often require
several days of open wound management before primary closure to ensure
all nonviable tissue has been declared before surgery (Fig. 2 ). The techniques
used for mammals can be applied to avian patients. Suture placement is
more critical in the avian patient to ensure proper tissue apposition [14,20].
Absorbable suture (2-0 to 5-0) with an atraumatic tapered needle is optimal
for muscle and subcutaneous tissue [14,20]. Reduction of dead space in the
wound area will aid in the healing process [3]. Chromic catgut is not
recommended for avian surgery due to the strong inflammatory reaction it
stimulates [15]. For prolonged wound healing, slowly absorbed mono-
filament suture material absorbed by hydrolysis is most appropriate [15].
The location of the wound will dictate the type of suture pattern used. For
primary closure of wounds in areas of high tension, such as the extremities,
a far-near-near-far pattern may be used to manage tension and achieve and
94 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

Fig. 2. Umbrella cockatoo with a crop fistula secondary to thermal injury. This patient was
syringe fed formula that was too hot, resulting in a full-thickness thermal injury to the
dependent area of the crop. The wound was managed open for 3 days to allow for declaration of
nonviable tissue before surgical debridement and closure.

maintain apposition of wound edges [14,16]. In the avian patient, tension and
potential tearing of tissues requires the use of more sutures per centimeter, less
intrinsic tension (within the suture loop), and atraumatic insertion [14].
Primary wound-healing time for most avian patients is 10 to 14 days for skin
healing [14]. Larger wounds or those under increased tension may require
longer healing.
In raptors, skin grafts and flaps have been used and proven effective in
closing large skin wound that are under high tension [21]. There is limited
information in the literature regarding the use of skin grafts or flaps in
psittacine birds. This may be due, in part, to the smaller patient size and
limited available skin tissue in companion avian patients compared with
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 95

raptors. A dorsal cervical single pedicle advancement flap was uses in three
birds with cranial skin defects with successful outcome [22].

Open-wound management
Wounds existing for greater than 8 hours when the patient initially presents
for evaluation are considered older wounds. Older or large-sized wounds are
often contaminated, requiring open-wound management. Wounds that
cannot be closed due to age or contamination or lack or adjacent tissue are
treated with open management (Figs. 3, 4, and 5). Healing occurs via second
intention healing. Open-wound therapy involves the use of topical medi-
cations or products and bandages. Open-wound management depends on
several factors: selection of a topical antimicrobial or wound healing
stimulant, use of various dressings, and placement of protective bandages
[16]. New products are being developed to aid in open-wound management,
and may function to accelerate the wound-healing process [16].
Wound contraction, the concentric reduction in size of an open wound, is
essential to second-intention healing (Fig. 6). Wound contraction is caused
by movement of fibroblasts in granulation tissue collagen and pulling forces
of granulation tissue myofibroblasts on the skin edges [17]. Numerous
factors affect wound contraction, including the amount of skin surrounding
the wound, pressure on the wound, and medications, dressings, and surgical
procedures that enhance or inhibit wound contraction [17].

Fig. 3. Adult umbrella cockatoo with self-inflicted medial tibiotarsal wound. The patient had
chewed at the limb and had removed the dermis and muscle tissue down to visible tendon.
Although the patient was presented within 2 hours of the injury, primary closure was not
possible due to lack of available adjacent dermal tissue for closure. If primary closure had been
attempted, excessive tension would have been created over the dorsal tibiotarsal area. This
wound was managed as an open wound. A padded bandage was placed over the limb and was
changed every 2 to 3 days.
96 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

Fig. 4. Same umbrella cockatoo as in Fig. 5. The medial tibiotarsal wound has healed
completely after 18 days of topical therapy and bandaging.

Topical products
As part of open-wound management, topical medications can be applied
to the wound area to promote healing and treat infected tissue. There are
many different types of ointments and topical products available on the
market for use [18]. A few of the more commonly used agents are included
in this discussion, and the reader is referred to the surgery and wound
literature for more extensive information.
Topical ointments can be a useful component to wound management.
Ointments can be water or oil based. In the avian patients, water-based
ointments are optimal [3,8]. Oil-based topical products, when used near

Fig. 5. Umbrella cockatoo with large, self-inflicted granulomatous wound in the pectoral
region.
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 97

Fig. 6. Sternal (keel) wound in an adult African gray parrot. This patient had a traumatic fall,
which caused the sternal wound. This wound was managed as an open wound that healed via
second intention. Note the patient is wearing a neck collar to prevent access to the wound area
during healing. (Courtesy of Connie Orcutt, DVM, Dipl. ABVP-Avian.)

a feathered area to which the avian patient has access, can end up being
preened into the feathering affecting thermoregulation. Topical antibiotic
ointment is indicated for use with an infected wound in conjunction with
systemic therapy when indicated. An example of an antibiotic ointment
often used in the mammalian and avian patients is a triple antibiotic
ointment containing bacitracin, neomycin, and polymixin (Neosporin
ointment, GalaxoSmithKline, Research Triangle Park, North Carolina).
This type of ointment has a broad spectrum of bactericidal activity, and can
also stimulate wound reepithelialization [16,18]. Potential negative effects
of a topical antibiotic ointment in the avian patient include potential for
systemic absorption and adverse side effects. This type of topical product is
best used in small wound areas.
98 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

Gentamicin sulfate ointment (Goldine Laboratories, Ft. Lauderdale,

Florida) has been demonstrated to be effective for controlling growth of
bacteria, especially Gram-negative bacteria [18]. This ointment is the topical
agent of choice for use with skin grafts because of its effective control of
Gram-negative bacteria [3,23]. Gentamicin has been shown to impair wound
contraction and epithelialization [18,23].
Another topical product with positive wound benefits in the avian patient
is silver sulfadiazine cream (Silvadene Crème, Boots Pharmaceuticals Inc.,
Lincolnshire, Illinois). This cream is effective against most Gram-positive
and Gram-negative bacteria and most fungi [18]. This makes it an ideal
product to use with open, infected wounds. Silver sulfadiazine cream also
promotes epithelialization, and is indicated for use with thermal burn
wounds due to its ability to penetrate necrotic and eschar tissue [18]. This
cream does have a negative effect on fibroblasts, which may impede wound
contraction [18]. Nitrofurazone in a polyethylene glycol base (Nitrofurazone,
The Butler Company, Columbus, Ohio) is used in mammals in the initial
stages of wounds to facilitate drainage of supporative exudates and decrease
edema [18]. Nitrofurazone has been shown to inhibit epithelialization in
mammals [18]. This product is not often used in birds due to this inhibition of
epithelialization. The caseous consistency of bird exudates makes this
product less effective than some other topical products [8,16].
There are many different types of wound dressing available for use in the
avian patient. Occlusive dressing products work well in avian wounds.
Occlusive dressings are polymers with a water content between 90% and
95%. These dressings are semitransparent, nonadherent, and are available
in the form of sheets or gels [17]. An example of a commercially available
polyethylene oxide occlusive dressing in a gel form is Biodres (DVM
Pharmaceuticals, Inc., Miami, Florida). This type occlusive dressing reduces
infection, promotes angiogenesis, epithelialization, and good wound
contraction in the avian patient (Fig. 7). This type of dressing is indicated
for open wounds in the repair stage with a healthy granulation bed and
decreased fluid production, and when epithelialization has begun [17].
Other examples of topical wound products used with avian wound
treatment include enzymatic debridement agents, live yeast cell derivatives,
softening agents, and topical wound-healing stimulants. Topical products
containing steroid medication should be used with caution in the avian
patient due to the potential for systemic absorption from topical application.
The potential immunosuppressive and other systemic side effects of steroid
use in the avian patient usually preclude the use topical application of steroid
medications.

Bandaging techniques
The type of bandage used will depend on the exact nature of the wound,
location, functional needs, and the patient. The primary dressing layer of
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 99

Fig. 7. Biodres dressing material. This material is a polyethylene oxide occlusive dressing in
a gel composition. The backing is being peeled away for application to the wound.

the bandage is usually used to debride necrotic debris and tissue, deliver
medication, transmit wound exudates, or form an occlusive seal over the
wound [17]. Both adherent and nonadherent primary dressings can be used
in the avian patient [8,16]. The type of primary dressing used depends on the
stage of healing. Adherent dressings function to help debride the wound and
absorb exudate. Adherent bandages are used during the initial inflammatory
stage of healing. The nonadherent bandage layer is usually used during the
proliferative and remodeling stages of healing [3,8,16]. Nonadherent
dressings provide protection from abrasion of the regenerating tissue during
bandage changes.
Nonadherent dressings can be occlusive or nonocclusive. The nonadherent
semiocclusive bandages retain moisture, which helps prevent dehydration of
tissues and promotes epithelialization. Excess fluid can also be absorbed from
the wound. There are many pad-type dressings available for use with avian
wounds. These pads can be purchased with various properties, and some
brands are impregnated with agents. Petrolatum-impregnated sponges or
fine-mesh gauze are available. These can be used when a bed of granulation
tissue is present, a serosanguinous exudate is being produced, or epithelial-
ization is occurring at the wound margins [17]. With nonadherent bandages,
the goal is to prevent damage to the new tissue during the bandage change
procedure. Cotton dressings can be used in birds, but if left in place for more
than 2 to 3 days tends to adhere to the wound [8,16]. This can lead to dis-
ruption and hemorrhage of the healing surface when the primary layer is
removed [3].
The secondary and tertiary layers of the bandage function to absorb
wound fluids and exudates, protect against physical shock, immobilize the
wound, and prevent contamination of the wound. These additional layers
100 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

can also serve to protect against self-mutilation [3,16]. The secondary layer is
usually a wrap that either provides padding or conforms to the specific
wound area. A durable and flexible material works best as a tertiary layer,
and functions to hold the bandage together. In psittacine birds the tertiary
layer needs to be a material that is resistant to chewing, as many companion
and aviary birds will be attracted to the bandage material. Elastic tape can be
used for the tertiary layer. Several examples of tertiary layer materials useful
in psittacine birds include an elastic tape with its own adhesive backing
(Elastikon Elastic Tape, Johnson and Johnson Medical Inc., New Bruns-
wick, New Jersey) or elastic, self-adhering wraps (Vetrap Bandaging Tape,
3M Animal Care Products, St. Paul, Minnesota). In psittacine birds an
outermost layer of adhesive tape (Zonas Porous Tape, Johnson and Johnson
Medical Inc., New Brunswick, New Jersey) provides an outer protective layer
that is resistant to damage from chewing. Raised tabs of tape often work well
as a distraction measure for avian patients focused on chewing at their own
bandages [3]. Neck collars are often necessary with psittacine patients to
prevent chewing and destruction of the bandage materials.
The bandage shape and components used are often modified for use in
specific anatomical areas. Wounds involving the extremities require modifi-
cation to provide optimal bandage function without excessive immobili-
zation. A figure-of-eight type bandage can be applied to the thoracic
limb [8]. This type of bandage keeps the joints in flexion. When applying
a bandage to the thoracic limb care must be used to avoid excessive patagial
constriction. Patagial constriction or prolonged immobilization may cause
irreversible contraction of the patagial tendon or vascular necrosis [8,16].
Return of flight function is crucial for aviary or wild birds that rely on flight
for survival. Wound on the feet often require a modified bandage to relieve
pressure, and if possible, allow for some level of perching function.
Interdigitating bandages, ‘‘donut’’ bandages and ball bandages can be
applied to the feet. These bandages help to protect wounds, relieve pressure,
and immobilize the digits [3,16] (Fig. 8).

Specific conditions/common presentations

Psittacine birds experience a wide variety of dermatologic conditions.
Many of the dermatologic diseases diagnosed in companion and aviary
birds result in skin and soft tissue abnormalities requiring wound care.
Some of the more common psittacine disease conditions having potential
to result in skin abnormalities and wounds include bacterial infection,
fungal infection, viral infection (poxvirus, circovirus, papovavirus), neo-
plasia (epithelial and mesenchymal), parasitic disease, feather cysts, nutri-
tional/metabolic disease, ulcerative dermatitis self-mutilation/feather picking,
hypersensitivity (not well documented in psittacines), thermal injury, deglov-
ing, frostbite, crop lacerations, digit constriction (Fig. 9) or amputation [24].
The reader is referred to the many other specific publications on companion
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 101

Fig. 8. Eclectus chick with an interdigitating padded foot bandage. This chick had the bandage
placed after having surgical treatment for constricted toe lesions.

and aviary bird dermatologic conditions when considering how to diagnose

and treat these conditions [1,24,25].

Emerging wound-treatment options

Nonhealing ulcerative extremity wounds are common in diabetic human
patients. The human medical community has investigated many forms of

Fig. 9. Adult female eclectus with severe constriction injury to the foot. This bird had access to
fraying cloth material causing constriction at the hock area. Digits one and three became
necrotic, requiring surgical amputation. A padded bandage was used on the foot for 3 weeks.
The bandage was changed every 3 days. The bird is now able to use the foot for perching.
102 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104

wound treatment and care in an attempt to promote adequate healing of

diabetic wounds. These diabetic wounds can become life-threatening,
leading to thousands of limb amputations annually [26,27].
Currently, more than a dozen angiogenesis-stimulating modalities are
being tested in human clinical trials sponsored by various biotechnology and
pharmaceutical companies, medical centers, and the US National Institute of
Health. The use of a topical recombinant human platelet derived growth
factor, becaplermin gel (Regranex Gel, Ortho-McNeil Pharmaceutical, Inc.,
Raritan, New Jersey) has been shown to be a safe and effective pro-angiogenic
therapy in humans. Treatment with the becaplermin gel has been shown to
decrease the time to complete healing of chronic, full-thickness, lower ex-
tremity diabetic neurotropic ulcers compared with placebo treatment [28]. In
1997, the United States Food and Drug Administration granted marketing
clearance for Regranex Gel (becaplermin) as the first biologic proven to in-
crease the incidence of complete healing in diabetic foot ulcers in humans [29].
Regranex Gel contains becaplermin, a recombinant human platelet-
derived growth factor (rh PDGF-BB) for topical administration. Becapler-
min is produced by recombinant DNA technology by insertion of the gene
for the B chain of platelet-derived growth factor (PDGF) into the yeast,
Saccharomyces cerevisiae. Regranex Gel is a nonsterile, low bioburden,
preserved, sodium carboxymethylcellulose-based topical gel, containing the
active ingredient becaplermin and several inactive ingredients [29].
The biologic activity of becaplermin is similar to that of naturally
occurring PDGF and includes promoting chemotactic recruitment and
proliferation of cells involved in the wound repair process. Animal studies
using the rh PDGF-BB recombinant human growth factor have shown that
rh PDGF-BB accelerates the wound-healing cascade by promoting the
growth of granulation tissue [28]. Platelet-derived growth factor stimulates
angiogenesis and stimulates and recruits macrophages, neutrophils (hetero-
phils in the case of avian patients), and fibroblasts; and stimulates
granulation tissue formation, wound contraction, and wound remodeling
[28]. The becaplermin gel binds very quickly (within a few minutes) to tissue
receptor sites, allowing for quick treatment and minimal patient stress. A
clinical pharmacokinetic study of topically administered rhPDGF-BB in
human patients with pressure ulcers has shown the recombinant product to
be minimally absorbed into the systemic circulation [30].
There are currently many companion avian patients that present with
mild to severe forms of ulcerative, nonhealing wounds of the extremities or
body. There is a syndrome in many species of psittacines of self-mutilation
and feather picking that may have a behavioral component. These patients
will often self-mutilate to the point of inflicting significant, nonhealing
ulcerative wounds of the dermis and underlying tissues. A common location
of these ulcerative wounds in the patagium, medial or lateral wings, neck,
pectoral area, back, base of the tail, legs, and feet. In some species of
psittacines such as lovebirds (Agapornis sp.) and Amazon parrots (Amazonia
 T.K. Ritzman / Vet Clin Exot Anim 7 (2004) 87–104 103

sp.), there is an ulcerative skin condition of unknown etiology (termed

cutaneous ulcerative disease) [24]. Many of these patients inflict wounds of
the dermis that require treatment that often includes debridement, control,
and treatment of secondary bacterial or fungal infection, direct bandaging,
and restriction of use of the extremity until healing has occurred.
Of particular challenge in avian patients is the treatment of chronic,
nonhealing ulcerative skin wounds of the medial wings and patagium. Due to
the normal dynamic movement of the muscles, tendons, and skin of the wings
during flight, normal extension and flexion of the wings cause constant
disruption of the wounds, delaying or preventing healing. Immobilization of
the limb is often required to allow healing. The disadvantage of long-term
immobilization of the thoracic limb is the prevention of flight and potential
permanent inability of the bird to extend the wing. A topical product that
could reduce the wound-healing time for the avian patients would be
invaluable in terms of reducing immobilization time and patient stress
associated with repeated handling and bandaging. This author is currently
investigating the effects of the use of becaplermin, a rh PDGF-BB, for topical
administration on noninfected, chronic avian wounds.

Summary
Psittacines and other companion avian species often develop wounds
requiring some form of medical or surgical therapy. Advancing technology in
the field of wound care and management continues to evolve for use by the
veterinary clinician. Although not all wounds can be successfully treated,
many can be reduced and minimized with therapy. Consideration of the
overall health, management, and nutrition of the avian patient will also aid in
wound management. The avian patient with normal immune function and
optimal nutrition will have improved wound healing compared with an
immunocompromized or malnourished patient. The duration of treatment
and potential stress of the wound-management program should also be taken
into consideration when selecting a treatment program for the avian patient.

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